and what's more, the eu imports most of its energy from russia, which is a top oil producer. should putin take the risk and turn off the taps, as he did with ukraine in 2009 and in 2006, it could spell disaster for europe and, perhaps, the u.s. as the "new republic" notes, "any supply shocks in europe that send prices higher will have ripple effects that raise gas prices in the united states." fiona hill is an expert on russia and eurasian affairs at the brookings institution. fiona, thanks for being here. let's start with that question. you do have a lot of criticism of the president saying that he needs to take stronger action. what conceivable stronger action could be taken? >> well, the problem is, as you've just laid out, that the strong action that the president can take really is very dependent on being in lock step with our european allies. the real impact of any sanctions would only be felt on russia if the eu and other key allies are with us in the way that we are all acting together in the sanctions against iran and our dispute over iran's nuclear program. so, if w